Replies

1. 
   Westchester | Dec 28, 2009 03:14pm | #1

   I think the 1800 or variable speed grinders are better for sharpening - not sure how to / or if you can re-wire.

   The white wheels are just as good as the blue - no need to spend the extra money for the blue.

   I don't use leather - rather compound on the buffing wheel for the final polish.

   Good Luck,

   SA

2. 
   popawheelie | Dec 28, 2009 06:02pm | #2

   If you want to buff something I've used buffing wheels.

   But if you want to take a wire edge off I'd do it by hand.

   You spend all that time honing an edge by hand and then power buff it off? Doesn't make sense to me.

   I hand strop my edges. It just takes a few strokes.

1. 
   Westchester | Dec 29, 2009 08:58am | #10

   I agree Pop - you can ruin the honed edge with extensive buffing. However following the removal of the wire edge on a flat stone - a quick buff with green compound results in a razor sharp edge.

   Leather is OK - just slower in accomplishing the same sharp result you get quicker from a light wheel buff -

   SA

1. 
   popawheelie | Dec 29, 2009 10:14am | #12

   I agree a quick buff done well works. Especially if you are in a hurry. Some people use their tools alot and need to speed up sharpening.

   I felt I should say something to the original poster because so many people can use buffing to sharpen tools.

   It's temping when you have a large buffing wheel parged up and ready to make a tool edge shinny.

   I know because I've done it.

1. 
   Westchester | Dec 29, 2009 10:39am | #13

   Yes - and think of the advantages polishing a gouge with a soft wheel and compound vs a flat leather strop

   Watch those fences !

   SA

3. 
   forestgirl | Dec 28, 2009 08:00pm | #3

   Walt, I just went through a 2-week-long agonizing process getting sharpening set up for my turning tools (those tools only, not for any other sharpening). Here are my blood-soaked words of wisdom:

   #1 -- get good wheels and make sure they are made for what you're doing. For instance, some wheels need high speed to function properly, and are not appropriate on slow-speed grinders (may be true of seeded gel, but I'm not certain). By "good wheel" I mean one that's well-balanced, round and flat when you buy it. The higher-end Norton wheels might fit the bill. If they don't, quite, see #2 below.

   Learn as much as you can about wheels before you buy. They come in different grits, different materials, and different degrees of hardness. Virtually anything decent has to be ordered online, so you want to be sure and get it right.

   #2 You may end up needing a balancing kit to get your wheels to run decently, especially for your turning tools. IMHO, it's a waste of time to try to sharpen a gouge when the wheel's wobbling all over the place and the tool's not getting a consistent contact. The Oneway balancing kit can be ordered for different shaft sizes, but can only be used with wheels that have a 1" or 1.25" arbor hole. It does nothing for a wheel that's not flat and does the hula-hoop dance when it spins.

   #3 From what I've gathered, a 60 or 80 grit, and a 120 grit will do fine for your turning tool set-up. I've used a pink and white, respectively, but there are other options. I will try to find the big discussion that was on the old Knots about this and link you to it.

4. 
   forestgirl | Dec 28, 2009 08:06pm | #4

   OK, I found it. Click here, and you'll go to the "Pink Wheel" thread, wherein I learned a ton about sharpening wheels. The reference to "SG" wheels is "seeded gel." I can't find the article right now, but I virtually certain in an excerpt from Leonard Lee's book on sharpening that he said the SG wheels are designed for high-speed grinding.

5. 
   lwilliams | Dec 28, 2009 08:43pm | #5

   First of all, proper dressing of wheels is the most important thing you can do to control the heat build-up from grinding. Secondly a coarse wheel will generate considerably less heat than a finer wheel. Technique is also critical to avoid excessive heat build up and proper technique is quite easy to learn.

   A high speed grinder makes it much easier to properly dress and true wheels than a slower grinder. For edge tools like chisels and plane irons, grinding is a shaping operation; you don't "sharpen" on a grinder. Turners have a different approach for turning tools but turning tools sharpened like chisels and plane irons work exceptionally well. The same can't be said for chisels and plane irons sharpened like many turners seem to do, chisels and plane irons simply need more attention.

   Get some 36 grit gray wheels (24 grit if you can find them) and a diamond dresser. I haven't tried the new blue wheels but they may be a good, but more expensive, alternative. Let these wheels do the work and don't force your tool into them, just light pressure. Also learn how to limit grinding all the way to the thin area at the edge by proper tool maintenance and by first establishing the location of a new cutting edge when more serious grinding is needed.

   I'm convinced that fear of grinding combined with improper equipment and improper technique is the single biggest barrier for woodworkers trying to learn to use and enjoy hand tools.

1. 
   WillGeorge | Dec 28, 2009 09:20pm | #6

   36 grit? Grinding concrete? Just funnin'

   Old metal worker and I know nothing about grinding wheels. I just asked for something at the tool makers shed.

   Not sure but I think (LONG AGO) the shop grinders we used were, maybe, 800 rpm or less? These were the grinders for hand work. Not the machine grinders.

   I believe you are serious with your statement, but my mind tells me 36 grit is wasting good HSS...

   I am NOT fighting you, really. I am only asking why you feel such an agressive grit is helpful. My first thought was many more stages to the final polish for the edge.

   I'll explain a bit about my thought. I have only one fine quality chisel. A 19 mm paring.. I could never bring myself to put it to a 36 grit wheel...

   Just a question here and no hate here at all!

   To me a 36/24 grit wheel was something to grind off a plug of cold rolled iron.. Not HSS..

1. 
   lwilliams | Dec 28, 2009 11:05pm | #8

   Will,

   Sharpening is done on honing stones. Again, grinding is a shaping operation only. I'm sure I can remove all the abrasive signatures of a 24 grit wheel at the cutting edge in just three or four passes on my medium India stone. Actually, I'd be hard-pressed to see the difference in grinding signatures of 24 grit and 60 grit wheels with the naked eye. However, I can easily tell the difference in the amount of heat each will generate while grinding. The heat difference is huge. Unlike honing where both planes that make up the cutting edge must be maintained, you're only grinding the bevel. I grind most bench chisels and plane irons at 25º and hone at 30º.

   BTW, you won't take off more steel with the coarse wheel. You'll just remove what's necessary in a faster and cooler manner. Always avoid grinding all the way to the cutting edge. When you must remove a nick or something, establish the location of the new cutting edge by grinding at 90º to the face of the tool. Then grind the new bevel but make sure to leave a hair line of the flat created when establishing the location of the edge. Even with a cool grinding 24 grit wheel it's difficult to grind all the way to the cutting edge without overheating the steel. With a finer grit wheel grinding all the way to the cutting edge is sure to result in overheating the steel.

1. 
   WillGeorge | Dec 28, 2009 11:23pm | #9

   I think I understood what you said!

2. 
   pek-r-wood | Jan 02, 2010 07:21am | #14

   Will, don't think of the
   Will, don't think of the 36-grit as "more aggressive", think of it as "slower to load up and glaze over". Not that it really makes much difference if you only grind a few tools every once in awhile, but if you do a lot a coarser wheel will grind cooler, alot longer.

6. 
   lwj2 | Dec 28, 2009 10:57pm | #7

   FG has some good advice.

   Buy good quality stones. I have a 60 and 100 grit set I purchhased (damned reply box is too effing small!) from Woodcraft.

   Get a diamond dresser -- mine is a single stone, there's a T-style available also.

   I suggest you look into the Veritas (Lee Valley) tool rest.

   My grinder turns at 3,450, I've used 1,725 also. The most important thing is a light touch -- keep your tools cool. I have a can of water handy to cool down tools, when whatever I'm sharpening gets warm, it gets a bath. A quick wipe-down with a paper towel takes care of the water, then another with a lightly-oiled rag.

   Have a happy new year and have fun!

1. 
   Walt71112 | Dec 29, 2009 09:52am | #11

   Wow! I really appreciate everyone's quick reply with so much information. I now feel much more prepared to setup my grinders and use them better.

   Thanks and have a Happy New Year!

   Walt

7. 
   BruceS | Jan 02, 2010 06:16pm | #15

   White wheels for HSS (Norton Premium Alundum/ very fine grit for my turning tools, Gray wheels for High carbon steel (Carbourndum 60 grit for general grinding, Green for carbide. and my Jet very slow wet grinder for chisles/plane iron roughing in the initial edge and then lapping the final edge on a glass plate using wet/dry paper to 1200 grit.

   3450 RPM induction motors can NOT be slowed.